<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <title>DB_TXN-&gt;commit()</title>
    <link rel="stylesheet" href="apiReference.css" type="text/css" />
    <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
    <link rel="start" href="index.html" title="Berkeley DB C API Reference" />
    <link rel="up" href="txn.html" title="Chapter 12.  The DB_TXN Handle" />
    <link rel="prev" href="txnabort.html" title="DB_TXN-&gt;abort()" />
    <link rel="next" href="txndiscard.html" title="DB_TXN-&gt;discard()" />
  </head>
  <body>
    <div xmlns="" class="navheader">
      <div class="libver">
        <p>Library Version 12.1.6.2</p>
      </div>
      <table width="100%" summary="Navigation header">
        <tr>
          <th colspan="3" align="center">DB_TXN-&gt;commit()</th>
        </tr>
        <tr>
          <td width="20%" align="left"><a accesskey="p" href="txnabort.html">Prev</a> </td>
          <th width="60%" align="center">Chapter 12. 
                The DB_TXN Handle 
        </th>
          <td width="20%" align="right"> <a accesskey="n" href="txndiscard.html">Next</a></td>
        </tr>
      </table>
      <hr />
    </div>
    <div class="sect1" lang="en" xml:lang="en">
      <div class="titlepage">
        <div>
          <div>
            <h2 class="title" style="clear: both"><a id="txncommit"></a>DB_TXN-&gt;commit()</h2>
          </div>
        </div>
      </div>
      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_TXN-&gt;commit(DB_TXN *tid, u_int32_t flags);  </pre>
      <p>
        The <code class="methodname">DB_TXN-&gt;commit()</code> method ends the transaction.
    </p>
      <p>
         In the case of nested transactions, if the transaction is a parent
         transaction, committing the parent transaction causes all unresolved
         children of the parent to be committed.  In the case of nested
         transactions, if the transaction is a child transaction, its locks are
         not released, but are acquired by its parent.  Although the commit of
         the child transaction will succeed, the actual resolution of the child
         transaction is postponed until the parent transaction is committed or
         aborted; that is, if its parent transaction commits, it will be
         committed; and if its parent transaction aborts, it will be aborted.
    </p>
      <p>
         All cursors opened within the transaction must be closed
         before the transaction is committed. If they are not closed,
         they will be closed by this function. When the close
         operation for a cursor fails, the method returns a non-zero
         error value for the first instance of such an error, closes
         the rest of the cursors, and then aborts the transaction.
         
     </p>
      <p>
         After <code class="methodname">DB_TXN-&gt;commit()</code> has been called, regardless of its return, the
         <a class="link" href="txn.html" title="Chapter 12.  The DB_TXN Handle">DB_TXN</a>  handle may not be
         accessed again.  If <code class="methodname">DB_TXN-&gt;commit()</code> encounters an error, the
         transaction and all child transactions of the transaction are aborted.
    </p>
      <p>
         The <code class="methodname">DB_TXN-&gt;commit()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
         The errors values that this method returns include the error values of the 
         <code class="methodname">DBcursor-&gt;close()</code> method and the following:
         
    </p>
      <div class="sect3" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h4 class="title"><a id="idm140711172167280"></a>DB_LOCK_DEADLOCK</h4>
            </div>
          </div>
        </div>
        <p>
                A transactional database environment operation was selected to resolve
                a deadlock.
            </p>
      </div>
      <div class="sect3" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h4 class="title"><a id="idm140711172137984"></a>DB_LOCK_NOTGRANTED</h4>
            </div>
          </div>
        </div>
        <p>
                A Berkeley DB Concurrent Data Store database environment configured
                for lock timeouts was unable to grant a lock in the allowed time.
            </p>
        <p>
                You attempted to open a database handle that is configured
                for no waiting exclusive locking, but the exclusive lock could not be
                immediately obtained. See
                <a class="xref" href="dbset_lk_exclusive.html" title="DB-&gt;set_lk_exclusive()">DB-&gt;set_lk_exclusive()</a>
                for more information.
            </p>
      </div>
      <div class="sect3" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h4 class="title"><a id="idm140711172105200"></a>DB_REP_LEASE_EXPIRED</h4>
            </div>
          </div>
        </div>
        <p>
                The operation failed because the site's replication master lease has expired.
            </p>
      </div>
      <div class="sect3" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h4 class="title"><a id="idm140711172102672"></a>EINVAL</h4>
            </div>
          </div>
        </div>
        <p>
                If the cursor is already closed; or if an invalid flag
                value or parameter was specified.
            </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140711172061408"></a>Parameters</h3>
            </div>
          </div>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idm140711172061024"></a>flags</h4>
              </div>
            </div>
          </div>
          <p>
                          The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
                          or one of the following values:
                     </p>
          <div class="itemizedlist">
            <ul type="disc">
              <li>
                <p>
                  <code class="literal">DB_TXN_NOSYNC</code>
            </p>
                <p>
                 Do not synchronously flush the log.  This means the transaction will
                 exhibit the ACI (atomicity, consistency, and isolation) properties,
                 but not D (durability); that is, database integrity will be
                 maintained, but it is possible that this transaction may be undone
                 during recovery.
            </p>
                <p>
                 This behavior may be set for a Berkeley DB environment using the
                 <a class="xref" href="envset_flags.html" title="DB_ENV-&gt;set_flags()">DB_ENV-&gt;set_flags()</a> 
                 method or for a single transaction using the 
                 <a class="xref" href="txnbegin.html" title="DB_ENV-&gt;txn_begin()">DB_ENV-&gt;txn_begin()</a>  method. 
                 Any value specified to this method overrides both of those settings.
            </p>
              </li>
              <li>
                <p>
                  <code class="literal">DB_TXN_SYNC</code>
            </p>
                <p>
                 Synchronously flush the log.  This means the transaction will exhibit
                 all of the ACID (atomicity, consistency, isolation, and durability)
                 properties.
            </p>
                <p>
                 This behavior is the default for Berkeley DB environments unless the
                 <a class="link" href="envset_flags.html#envset_flags_DB_TXN_NOSYNC">DB_TXN_NOSYNC</a> 
                 flag was specified to the 
                 <a class="xref" href="envset_flags.html" title="DB_ENV-&gt;set_flags()">DB_ENV-&gt;set_flags()</a>  method.
                  This behavior may also be set for a single transaction using the
                 <a class="xref" href="txnbegin.html" title="DB_ENV-&gt;txn_begin()">DB_ENV-&gt;txn_begin()</a> 
                 method.  Any value specified to this method overrides both of those
                 settings.
            </p>
              </li>
              <li>
                <p>
                  <code class="literal">DB_TXN_WRITE_NOSYNC</code>
            </p>
                <p>
                 Write but do not synchronously flush the log on
                 transaction commit. This means that transactions
                 exhibit the ACI (atomicity, consistency, and
                 isolation) properties, but not D (durability); that
                 is, database integrity will be maintained, but if the
                 system fails, it is possible some number of the most
                 recently committed transactions may be undone during
                 recovery.  The number of transactions at risk is
                 governed by how often the system flushes dirty
                 buffers to disk and how often the log is
                 checkpointed.
            </p>
                <p>
                This form of commit protects you against application
                crashes, but not against OS crashes. This method
                offers less room for the possiblity of data loss than
                does <code class="literal">DB_TXN_NOSYNC</code>.
            </p>
                <p>
                 This behavior may be set for a Berkeley DB environment using the
                 <a class="xref" href="envset_flags.html" title="DB_ENV-&gt;set_flags()">DB_ENV-&gt;set_flags()</a> 
                 method or for a single transaction using the 
                 <a class="xref" href="txnbegin.html" title="DB_ENV-&gt;txn_begin()">DB_ENV-&gt;txn_begin()</a>  method. 
                 Any value specified to this method overrides both of those settings.
            </p>
              </li>
            </ul>
          </div>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140711172053312"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>, <a class="link" href="txn.html" title="Chapter 12.  The DB_TXN Handle">DB_TXN</a> 
            </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140711172098080"></a>See Also</h3>
            </div>
          </div>
        </div>
        <p>
                     <a class="xref" href="txn.html#txnlist" title="Transaction Subsystem and Related Methods">Transaction Subsystem and Related Methods</a> 
                </p>
      </div>
    </div>
    <div class="navfooter">
      <hr />
      <table width="100%" summary="Navigation footer">
        <tr>
          <td width="40%" align="left"><a accesskey="p" href="txnabort.html">Prev</a> </td>
          <td width="20%" align="center">
            <a accesskey="u" href="txn.html">Up</a>
          </td>
          <td width="40%" align="right"> <a accesskey="n" href="txndiscard.html">Next</a></td>
        </tr>
        <tr>
          <td width="40%" align="left" valign="top">DB_TXN-&gt;abort() </td>
          <td width="20%" align="center">
            <a accesskey="h" href="index.html">Home</a>
          </td>
          <td width="40%" align="right" valign="top"> DB_TXN-&gt;discard()</td>
        </tr>
      </table>
    </div>
  </body>
</html>
